[RFC PATCH 2/2] drivers: pwm: pwm-atmel: add support for pwm modes
Claudiu Beznea
claudiu.beznea at microchip.com
Wed Apr 5 06:58:59 PDT 2017
Implement pwm modes by adding PWM controller specific
configuration. Since this driver is used by controllers
which supports PWM push-pull mode and controllers which
doesn't, a new field was added in driver private data
structure. Also, the driver private data structure was
changed to adapt the new feature.
Signed-off-by: Claudiu Beznea <claudiu.beznea at microchip.com>
---
drivers/pwm/pwm-atmel.c | 94 +++++++++++++++++++++++++++++++++----------------
1 file changed, 63 insertions(+), 31 deletions(-)
diff --git a/drivers/pwm/pwm-atmel.c b/drivers/pwm/pwm-atmel.c
index 530d7dc..9e812ce 100644
--- a/drivers/pwm/pwm-atmel.c
+++ b/drivers/pwm/pwm-atmel.c
@@ -33,8 +33,11 @@
#define PWM_CMR 0x0
/* Bit field in CMR */
-#define PWM_CMR_CPOL (1 << 9)
-#define PWM_CMR_UPD_CDTY (1 << 10)
+#define PWM_CMR_CPOL BIT(9)
+#define PWM_CMR_UPD_CDTY BIT(10)
+#define PWM_CMR_DTHI BIT(17)
+#define PWM_CMR_DTLI BIT(18)
+#define PWM_CMR_PPM BIT(19)
#define PWM_CMR_CPRE_MSK 0xF
/* The following registers for PWM v1 */
@@ -65,11 +68,16 @@ struct atmel_pwm_registers {
u8 duty_upd;
};
+struct atmel_pwm_data {
+ struct atmel_pwm_registers regs;
+ bool ppm_supported;
+};
+
struct atmel_pwm_chip {
struct pwm_chip chip;
struct clk *clk;
void __iomem *base;
- const struct atmel_pwm_registers *regs;
+ const struct atmel_pwm_data *data;
unsigned int updated_pwms;
/* ISR is cleared when read, ensure only one thread does that */
@@ -150,15 +158,15 @@ static void atmel_pwm_update_cdty(struct pwm_chip *chip, struct pwm_device *pwm,
struct atmel_pwm_chip *atmel_pwm = to_atmel_pwm_chip(chip);
u32 val;
- if (atmel_pwm->regs->duty_upd ==
- atmel_pwm->regs->period_upd) {
+ if (atmel_pwm->data->regs.duty_upd ==
+ atmel_pwm->data->regs.period_upd) {
val = atmel_pwm_ch_readl(atmel_pwm, pwm->hwpwm, PWM_CMR);
val &= ~PWM_CMR_UPD_CDTY;
atmel_pwm_ch_writel(atmel_pwm, pwm->hwpwm, PWM_CMR, val);
}
atmel_pwm_ch_writel(atmel_pwm, pwm->hwpwm,
- atmel_pwm->regs->duty_upd, cdty);
+ atmel_pwm->data->regs.duty_upd, cdty);
}
static void atmel_pwm_set_cprd_cdty(struct pwm_chip *chip,
@@ -168,9 +176,9 @@ static void atmel_pwm_set_cprd_cdty(struct pwm_chip *chip,
struct atmel_pwm_chip *atmel_pwm = to_atmel_pwm_chip(chip);
atmel_pwm_ch_writel(atmel_pwm, pwm->hwpwm,
- atmel_pwm->regs->duty, cdty);
+ atmel_pwm->data->regs.duty, cdty);
atmel_pwm_ch_writel(atmel_pwm, pwm->hwpwm,
- atmel_pwm->regs->period, cprd);
+ atmel_pwm->data->regs.period, cprd);
}
static void atmel_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm,
@@ -223,9 +231,10 @@ static int atmel_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm,
if (state->enabled) {
if (cstate.enabled &&
cstate.polarity == state->polarity &&
- cstate.period == state->period) {
+ cstate.period == state->period &&
+ cstate.mode == state->mode) {
cprd = atmel_pwm_ch_readl(atmel_pwm, pwm->hwpwm,
- atmel_pwm->regs->period);
+ atmel_pwm->data->regs.period);
atmel_pwm_calculate_cdty(state, cprd, &cdty);
atmel_pwm_update_cdty(chip, pwm, cdty);
return 0;
@@ -258,6 +267,23 @@ static int atmel_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm,
val &= ~PWM_CMR_CPOL;
else
val |= PWM_CMR_CPOL;
+
+ /* PWM mode. */
+ if (atmel_pwm->data->ppm_supported) {
+ if (state->mode == PWM_MODE_PUSH_PULL) {
+ val |= PWM_CMR_PPM;
+ if (state->polarity == PWM_POLARITY_NORMAL)
+ val = (val & ~PWM_CMR_DTHI) |
+ PWM_CMR_DTLI;
+ else
+ val = (val & ~PWM_CMR_DTLI) |
+ PWM_CMR_DTHI;
+ } else {
+ val &= ~(PWM_CMR_PPM | PWM_CMR_DTLI |
+ PWM_CMR_DTHI);
+ }
+ }
+
atmel_pwm_ch_writel(atmel_pwm, pwm->hwpwm, PWM_CMR, val);
atmel_pwm_set_cprd_cdty(chip, pwm, cprd, cdty);
mutex_lock(&atmel_pwm->isr_lock);
@@ -277,27 +303,33 @@ static const struct pwm_ops atmel_pwm_ops = {
.owner = THIS_MODULE,
};
-static const struct atmel_pwm_registers atmel_pwm_regs_v1 = {
- .period = PWMV1_CPRD,
- .period_upd = PWMV1_CUPD,
- .duty = PWMV1_CDTY,
- .duty_upd = PWMV1_CUPD,
+static const struct atmel_pwm_data atmel_pwm_data_v1 = {
+ .regs = {
+ .period = PWMV1_CPRD,
+ .period_upd = PWMV1_CUPD,
+ .duty = PWMV1_CDTY,
+ .duty_upd = PWMV1_CUPD,
+ },
+ .ppm_supported = false,
};
-static const struct atmel_pwm_registers atmel_pwm_regs_v2 = {
- .period = PWMV2_CPRD,
- .period_upd = PWMV2_CPRDUPD,
- .duty = PWMV2_CDTY,
- .duty_upd = PWMV2_CDTYUPD,
+static const struct atmel_pwm_data atmel_pwm_data_v2 = {
+ .regs = {
+ .period = PWMV2_CPRD,
+ .period_upd = PWMV2_CPRDUPD,
+ .duty = PWMV2_CDTY,
+ .duty_upd = PWMV2_CDTYUPD,
+ },
+ .ppm_supported = true,
};
static const struct platform_device_id atmel_pwm_devtypes[] = {
{
.name = "at91sam9rl-pwm",
- .driver_data = (kernel_ulong_t)&atmel_pwm_regs_v1,
+ .driver_data = (kernel_ulong_t)&atmel_pwm_data_v1,
}, {
.name = "sama5d3-pwm",
- .driver_data = (kernel_ulong_t)&atmel_pwm_regs_v2,
+ .driver_data = (kernel_ulong_t)&atmel_pwm_data_v2,
}, {
/* sentinel */
},
@@ -307,20 +339,20 @@ MODULE_DEVICE_TABLE(platform, atmel_pwm_devtypes);
static const struct of_device_id atmel_pwm_dt_ids[] = {
{
.compatible = "atmel,at91sam9rl-pwm",
- .data = &atmel_pwm_regs_v1,
+ .data = &atmel_pwm_data_v1,
}, {
.compatible = "atmel,sama5d3-pwm",
- .data = &atmel_pwm_regs_v2,
+ .data = &atmel_pwm_data_v2,
}, {
.compatible = "atmel,sama5d2-pwm",
- .data = &atmel_pwm_regs_v2,
+ .data = &atmel_pwm_data_v2,
}, {
/* sentinel */
},
};
MODULE_DEVICE_TABLE(of, atmel_pwm_dt_ids);
-static inline const struct atmel_pwm_registers *
+static inline const struct atmel_pwm_data*
atmel_pwm_get_driver_data(struct platform_device *pdev)
{
const struct platform_device_id *id;
@@ -330,18 +362,18 @@ atmel_pwm_get_driver_data(struct platform_device *pdev)
id = platform_get_device_id(pdev);
- return (struct atmel_pwm_registers *)id->driver_data;
+ return (struct atmel_pwm_data *)id->driver_data;
}
static int atmel_pwm_probe(struct platform_device *pdev)
{
- const struct atmel_pwm_registers *regs;
+ const struct atmel_pwm_data *data;
struct atmel_pwm_chip *atmel_pwm;
struct resource *res;
int ret;
- regs = atmel_pwm_get_driver_data(pdev);
- if (!regs)
+ data = atmel_pwm_get_driver_data(pdev);
+ if (!data)
return -ENODEV;
atmel_pwm = devm_kzalloc(&pdev->dev, sizeof(*atmel_pwm), GFP_KERNEL);
@@ -373,7 +405,7 @@ static int atmel_pwm_probe(struct platform_device *pdev)
atmel_pwm->chip.base = -1;
atmel_pwm->chip.npwm = 4;
- atmel_pwm->regs = regs;
+ atmel_pwm->data = data;
atmel_pwm->updated_pwms = 0;
mutex_init(&atmel_pwm->isr_lock);
--
2.7.4
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